Psychological distress and the development of hypertension over 5 years in black South Africans.

Alarming increases in the incidence of hypertension in many low- and middle-income countries are related to alcohol overuse. It is unclear whether alcohol overuse is a symptom of psychological distress. The authors assessed psychological distress in Africans and its relationship with a 5-year change in blood pressure (BP), independent of alcohol intake. The authors followed 107 Africans with optimal BP (≤120/80 mm Hg) (aged 35-75 years) over 5 years. Alcohol intake (self-report and serum γ-glutamyl transferase) and nonspecific psychological distress (Kessler Screening Scale for Psychological Distress [K6]) were assessed. The K6 predicted hypertension development (P=.019), and its individual component "nervous" increased a participant's risk two-fold to become hypertensive (hazard ratio, 2.00 [1.23-3.26]). By entering K6 and γ-glutamyl transferase into multivariable-adjusted regression models for change in systolic BP, both were independently associated with change in systolic BP. Psychological distress and scoring high on being nervous predicted the development of hypertension over 5 years, independent of alcohol intake.